Device Tree

The device tree of USB is stored in the following path:

linux-5.15/arch/riscv/boot/dts/starfive/

The following is an example of the USB configuration in the file jh7110-common.dtsi.

&usbdrd30 {
        pinctrl-names = "default";
        pinctrl-0 = <&usb_pins>;
        dr_mode = "host"; /*host or peripheral*/
        status = "disabled";
 };

The following is an example of the USB configuration in the file jh7110.dtsi.

usbdrd30: usbdrd{
compatible = "starfive,jh7110-cdns3";
         reg = <0x0 0x10210000 0x0 0x1000>,
                   <0x0 0x10200000 0x0 0x1000>;
         clocks = <&clkgen JH7110_USB_125M>,
                       <&clkgen JH7110_USB0_CLK_APP_125>,
                       <&clkgen JH7110_USB0_CLK_LPM>,
                        <&clkgen JH7110_USB0_CLK_STB>,
                        <&clkgen JH7110_USB0_CLK_USB_APB>,
                        <&clkgen JH7110_USB0_CLK_AXI>,
                        <&clkgen JH7110_USB0_CLK_UTMI_APB>,
                        <&clkgen JH7110_PCIE0_CLK_APB>;
           clock-names = "125m","app","lpm","stb","apb","axi","utmi", "phy";
           resets = <&rstgen RSTN_U0_CDN_USB_PWRUP>,
                         <&rstgen RSTN_U0_CDN_USB_APB>,
                         <&rstgen RSTN_U0_CDN_USB_AXI>,
                         <&rstgen RSTN_U0_CDN_USB_UTMI_APB>,
                          <&rstgen RSTN_U0_PLDA_PCIE_APB>;
             reset-names = "pwrup","apb","axi","utmi", "phy";
             starfive,stg-syscon = <&stg_syscon 0x4 0xc4 0x148 0x1f4>;
             starfive,sys-syscon = <&sys_syscon 0x18>;
             status = "disabled";
             #address-cells = <2>;
             #size-cells = <2>;
             #interrupt-cells = <1>;
             ranges;
             usbdrd_cdns3: usb@10100000 {
                   compatible = "cdns,usb3";
                   reg = <0x0 0x10100000 0x0 0x10000>,
                              <0x0 0x10110000 0x0 0x10000>,
                              <0x0 0x10120000 0x0 0x10000>;
                    reg-names = "otg", "xhci", "dev";
                    interrupts = <100>, <108>, <110>;
                    interrupt-names = "host", "peripheral", "otg";
                    phy-names = "cdns3,usb3-phy", "cnds3,usb2-phy";
                    maximum-speed = "super-speed";
             };
 };

The following list provides an example of the parameters contained in the code block above.

• reg: The basic address and the max offset of the module.
• clocks: The clocks used by the module. Usually, this parameter is filled with the system clock source or the clock of the module.
• resets: The reset items used by the module.
• starfive,stg-syscon: The register values for the StarFive STG SYSCON control registers.
• starfive,sys-syscon: The register values for the StarFive SYS SYSCON control registers.
• status: The status of the module.
  • okay: The module is enabled.
  • disabled: The module is disabled.
• other: Other parameters for USB registration and association.